A method of analysis is shown of dynamical characteristics of the vibration system containing the mechanism with nonlinear transformation, of which the frequency characteristics are obtained and the linearized model expressing approximately this system is presented.
When the relation between the input and the output of mechanism is expressed as x₂=B_x1+a sin A_x1, the vibration with frequency ω, which is the rotational velocity, is produced in both input and output axes. The resonance exists at the frequency which is the simple function of masses and spring. In this case, the harmonic resonances having sharp peaks also exist. When the relation is expressed as x₂=a sin A_x1, the vibration with frequency 2ω exists in input axis, and the resonant frequency is the same as that of linear system of the output axis. These frequency characteristics are ascertained by the simulation using digital and hybrid computers.
The vibration system containing the mechanism with nonlinear transformation can be approximately expressed by the simple linearized model, of which the frequency characteristics, show good coincidence with that of nonlinear system. It facilitates the treatment of greater system, utilizing this linearized model.

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[in Japanese]

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In this paper, the static behavior of the bolted joint deformation is examined and the effect of that behavior on the loading point displacement of a column whose neutral axis is perpendicular to the joint interface is discussed. The flange displacement is measured by using strain gauge type pickups to observe the joint deformation. From this study, the following results are obtained. The behavior of the joint deflection has an important effect upon the loading point displacement, and the effect becomes more important when the joint interface starts to part. This joint deformation is formed from the sinuous deformation and the transverse deformation. In addition, the former is composed of the deflection of flange and bolt, and the sinking of the edge of flange into the base. There is an optimal point to bolt for the sinuous deformation of joint, which is determined by the interrelation between the bolt stiffness and the flange stiffness. Regarding the flange part as a beam of stepwise changing cross section on the elastic foundation, the sinuous deformation of joint can be nearly analyzed within the range where the joint interface does not start to part.

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Decision is often made at the shops whether the cutting conditions were suitable or not by observing the temper color on the steel chips. For the purpose of theorizing this convenient method, this paper analyzes the cooling behavior and the thickness of the oxide film on the chips and presents a calculating nomograph showing the cutting temperature by the temper color on the continuous chips. Here, the temper color is represented numerically by the thickness Fe₃O₄ film using the result of the previous paper. First, using the theoretical solution of cooling of a square rod with infinite length and the result of model experiments, the cooling velocity of chip is given by the equation consisting of its cross section size, its flowing velocity, its curling form and others. Next, the thickness of the oxide film on the cooling chip is obtained by expanding the calculating method of the oxide film produced by the diffusion at a constant temperature to the nonsteady state. Beside, the relation between the mean chip temperature and the tool face temperature is derived theoretically and experimentally. Consequently, the cutting temperature is obtained from the temper color, the cutting condition, the chip form and its size. But, this paper deals with the situations of dry cutting of carbon steel (S15C) at relatively high speed (i.e. from 50 to 200 m/min for 0.5 mm deformed chip thickness).

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To investigate the microstructure of work-deformed surface layer, high purity (001) single crystal surfaces of Al and Cu were scratched with diamond cones and dislocation structures under the scratch groove were observed through electron microscopes.
The results obtained are as follows:
(1) The dislocation structure inside of the groove is found to be composed of cell structures and the dislocation structure outside of the groove is similar to that found in the tensile deformation. These structures are slightly different for Al and Cu due probably to the difference in the stucking fault energy.
(2) It can be mentioned that the central part of the groove has suffered from the heavy deformation similar to that induced by cold-rolling or drawing, and thus cell structures are formed.
(3) As the cone angle of diamond stylus becomes smaller, the misorientation among neighboring cells becomes large and the deformed structure becomes polycrystalline.

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This paper proposes a dressing attachment forming a grind wheel along an involute curve by means of N.C. controllers, and the first method forming a grind wheel in the orthogonal coordinate system by means of two pulse motors, and the second one compensating the deviation from the circular arc and the tooth profile by the fine movement of the dressing attachment in the direction of the axis of the work gear, what you call "the dressing attachment based on the movement of the circular arc, " are compared and discussed. Using the former method, the mechanical errors of the dressing attachment almost become tooth profile's error. In the latter one, placing the dressing attachment so that the circular arc is approximated fairly well to the involute curve, the compensating mechanism doesn't need high accuracy. Further, using the diamond dresser, whose radius of roundness is less than 0.5 mm, the quantity interfering the grind wheel on account of the dresser's roundness is less than 1 μm, when the work gear is the standard spur gear, whose pressure angle is 20 degrees, and the number of teeth is more than 30. The dressing attachment based on the movement on the circular arc having some advantages is proposed and how to design this one is mentioned.

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An analytical consideration on the face grinding mechanism is made by statistical method. As the result, the theoretical equations for the rate of effective cutting edges and the distribution of grain depth of cut, grain cutting area and roughness of ground surface in the perpendicular section to grinding direction are obtained.
Furthermore, in order to estimate the influence of elastic displacement of grain cutting edges on them, Monte-Carlo simulation is performed. As the result, it is found that the existence of elastic displacement of grain cutting edges increases the number of effective cutting edges but has a little effect on the roughness of ground surface.

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It has been said that the high power density electron beam drilling is performed by the heating inside the target which is caused by the phenomenon that the high potential electrons penetrate into target. However, from the view-points of heat conduction theory and dynamic theory it has not been made clear. In this paper, the mechanism of high power density electron beam drilling of metals is discussed on the bases of heat conduction and force balance between vapour pressure and shrinking pressure due to surface tension. Namely, the critical temperature of generation of molten metal removal and the drilling speed are estimated. The estimated speed coincides with the experimental value. Moreover, the phenomenon of saturation of drilled depth is explained rationally.

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With the object of contribution to the security from bursting of the grinding wheels, bending strengths are investigated on the WA 60 vitrified sticks of some characteristic specifications in the ordinary and the static fatigue test under various basic grinding fluids. The sticks made of sharp shaped grains have smaller dispersion in the observed strength and fatigue life than the sticks made of round ones. This chiefly depends on the pore shape. The strengths and fatigue lives in various fluids decrease in the descending order of spindle oil or its compound oil with oleic acid, air, water, water solution of sodium nitrite and that of surfactants. These lowerings of strength and time to fracture might with great propriety be considered to result from attack of water molecules in the atmosphere to the tip of flaw under tensile stress as approved on the same phenomenon observed in alkaline silicate glasses. The strength of sticks used PbO type bonding material is more affected by water in a short time than that of Li₂O type one, and differs about 20% at the both ends of the above fluid order. Generally, the fracture path runs without regard to bond or grain.

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